CN115667415B

CN115667415B - Light-transmitting resin composition for laser welding, composition combination, molded article, and method for producing molded article

Info

Publication number: CN115667415B
Application number: CN202180037763.1A
Authority: CN
Inventors: 冈元章人
Original assignee: Mitsubishi Global Polyoxymethylene Co ltd
Current assignee: Mitsubishi Global Polyoxymethylene Co ltd
Priority date: 2020-05-25
Filing date: 2021-05-20
Publication date: 2023-12-29
Anticipated expiration: 2041-05-20
Also published as: JPWO2021241381A1; CN115667415A; EP4159815A1; EP4159815A4; KR20230015883A; WO2021241381A1

Abstract

The invention provides a light-transmitting resin composition for laser welding, a composition combination, a molded product and a method for manufacturing the molded product, wherein the color migration of a colorant to other components is inhibited. A light-transmitting resin composition for laser welding, which comprises 10-120 parts by mass of a reinforcing filler, 0.01-1.0 parts by mass of a light-transmitting pigment having a perylene skeleton, and at least one of a copper compound, an alkali halide, and cerium oxide, per 100 parts by mass of a crystalline thermoplastic resin.

Description

Light-transmitting resin composition for laser welding, composition combination, molded article, and method for producing molded article

Technical Field

The present invention relates to a light-transmitting resin composition for laser welding, a composition, a molded article, and a method for producing a molded article.

Background

Thermoplastic resins are easily processed and are widely used for parts of vehicles, parts of electric/electronic equipment, parts of other precision instruments, and the like, by utilizing their excellent properties. Recently, a member having a complicated shape may be produced from a thermoplastic resin, particularly a crystalline thermoplastic resin, and various welding techniques such as adhesive welding, vibration welding, ultrasonic welding, thermal plate welding, injection welding, and laser welding techniques may be used for bonding a member having a hollow portion such as an intake manifold.

However, the welding by the adhesive loses time until curing, and there is a problem of environmental burden such as environmental pollution. Problems have been pointed out such as damage to products, abrasion of powder, burrs, and the like due to vibration and heat, and the need for post-treatment. In addition, in many cases, injection welding requires a special mold or molding machine, and there are problems such as being unusable when the fluidity of the material is poor.

On the other hand, laser welding is a method of joining two resin members by bringing a resin member having a transmissivity to laser light (hereinafter, also referred to as a non-absorptivity and a weakly absorptivity) (hereinafter, also referred to as a "transmissive resin member") into contact with and welding a resin member having an absorptivity to laser light (hereinafter, also referred to as an "absorptive resin member"). Specifically, the method is a method of irradiating laser light from the side of the transmission resin member to the joining surface, and melting the absorption resin member forming the joining surface by the energy of the laser light to join the members. Since the laser welding does not generate abrasion powder or burrs and causes little damage to the product, and since the polyamide resin itself is a material having a high laser transmittance, the processing of the polyamide resin product by the laser welding technique has recently been attracting attention.

The transmissive resin member may be generally obtained by molding a light-transmissive resin composition. As such a light-transmitting resin composition, patent document 1 discloses a resin composition for laser welding, which comprises (B) 1 to 150 parts by mass of a reinforcing filler having a refractive index of 1.560 to 1.600 at 23 ℃ and (B) 100 parts by mass of a polyamide resin, wherein at least one monomer constituting at least one of the polyamide resins (a) contains an aromatic ring. In the example of patent document 1, a resin composition in which glass fibers and a colorant are blended in a mixture of polyamide MXD6 and polyamide 66 or a mixture of polyamide 6I/6T and polyamide 6 is disclosed.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 2008-308526

Disclosure of Invention

Problems to be solved by the invention

Here, as laser welding technology advances, new materials are further required. In particular, a material capable of suppressing color migration of the light-transmitting pigment in the transmissive resin member to other members (peripheral members) after laser welding is required.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a light-transmitting resin composition for laser welding, a composition, a molded article, and a method for producing a molded article, wherein migration of a colorant to other members is suppressed.

Means for solving the problems

Based on the above-described problems, the present inventors have studied and found that the above-described problems are solved by using a light-transmitting dye having a perylene skeleton as the light-transmitting dye.

Specifically, the above problems are solved by the following method.

1 > a light-transmitting resin composition for laser welding comprising 10 to 120 parts by mass of a reinforcing filler, 0.01 to 1.0 parts by mass of a light-transmitting pigment having a perylene skeleton, and at least one of a copper compound, an alkali halide and cerium oxide, per 100 parts by mass of a crystalline thermoplastic resin.

< 2 > the resin composition according to < 1 >, wherein,

the lanthanum content in the resin composition exceeds 0 mass ppm and is 40 mass ppm or less.

The resin composition of < 3 > according to < 1 > or < 2 > contains cerium oxide having a lanthanum content of more than 0 mass% and 1 mass% or less as measured by ICP emission spectrometry.

A resin composition according to any one of < 1 > - < 3 >, wherein,

the content of the cerium oxide in the resin composition is 0.01 to 5 mass%.

A resin composition according to any one of < 1 > < 4 >,

The crystalline thermoplastic resin contains a polyamide resin.

< 6 > the resin composition according to < 5 >, wherein,

the polyamide resin contains structural units derived from diamine and structural units derived from dicarboxylic acid, wherein 70 mol% or more of the structural units derived from diamine are derived from xylylenediamine, and 70 mol% or more of the structural units derived from dicarboxylic acid are derived from an alpha, omega-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms.

A resin composition according to any one of < 1 > < 6 >,

the light-transmitting dye having a perylene skeleton is a pigment.

< 8 > a combination of compositions having:

a resin composition according to any one of < 1 > - < 7 >, and

a light-absorbing resin composition comprising a thermoplastic resin and a light-absorbing pigment.

A molded article comprising the resin composition of any one of < 1 > - < 7 > or the combination of the resin compositions of < 8 >.

The molded article of < 10 > according to < 9 >, which is an in-vehicle camera part.

< 11 > an in-vehicle camera comprising the molded article of < 10 >.

< 12 > a method for producing a molded article, comprising:

A molded article formed from the resin composition of any one of < 1 > - < 7 > and a molded article formed from a light-absorbing resin composition comprising a thermoplastic resin and a light-absorbing pigment are laser welded.

ADVANTAGEOUS EFFECTS OF INVENTION

The present invention can provide a light-transmitting resin composition for laser welding, which suppresses color migration of a colorant to other members, and a composition, a molded article, and a method for producing a molded article.

Detailed Description

Hereinafter, a mode for carrying out the present invention (hereinafter, simply referred to as "present embodiment") will be described in detail. The present embodiment described below is an example for explaining the present invention, and the present invention is not limited to the present embodiment.

In the present specification, "to" is used in a sense including values described before and after the "to" as a lower limit value and an upper limit value.

In the present specification, unless otherwise specified, various physical property values and characteristic values are values at 23 ℃.

In the present specification, ppm refers to mass ppm.

The light-transmitting resin composition for laser welding (hereinafter, may be simply referred to as "resin composition") of the present embodiment includes: the thermoplastic resin composition comprises a crystalline thermoplastic resin, a reinforcing filler, a light-transmitting dye having a perylene skeleton, and at least one of a copper compound, an alkali halide, and cerium oxide, wherein the reinforcing filler is contained in an amount of 10 to 120 parts by mass and the light-transmitting dye having a perylene skeleton is contained in an amount of 0.01 to 1.0 part by mass relative to 100 parts by mass of the crystalline thermoplastic resin. With such a configuration, the color migration of the light-transmitting pigment to other members can be effectively suppressed.

Among the copper compound, the alkali halide, and the cerium oxide, the resin composition of the present embodiment preferably contains at least cerium oxide.

< crystalline thermoplastic resin >)

The resin composition of the present embodiment contains a crystalline thermoplastic resin. By using the crystalline thermoplastic resin, a resin composition having properties required for laser welding inherent in the crystalline thermoplastic resin can be obtained. Specifically, the crystalline thermoplastic resin has low water absorption, is less likely to cause variation in heat shrinkage due to mold temperature or the like, and has high mechanical strength.

As the crystalline thermoplastic resin, a polyamide resin, a crystalline polyester resin, and the like can be exemplified, and a polyamide resin is preferable.

The polyamide resin is a polymer having, as a repeating unit, an amide obtained by ring-opening polymerization of a lactam, polycondensation of an aminocarboxylic acid, and polycondensation of a diamine and a dibasic acid, and specifically includes: polyamide 6, polyamide 11, polyamide 12, polyamide 46, polyamide 66, polyamide 610, polyamide 612, polyamide 1010, polyamide 1012, polyamide 6I, polyamide 6/66, polyamide 6T/6I, polyamide 6/6T, polyamide 66/6T/6I, polytrimethylhexamethyleneterephthalamide, poly bis (4-aminocyclohexyl) methane lauramide, poly bis (3-methyl-4-aminocyclohexyl) methane lauramide, poly undecylenehexahydroterephthalamide, xylylenediamine polyamide resins described later, and the like. The above "I" represents an isophthalic acid component, and the "T" represents a terephthalic acid component.

As the polyamide resin used in the present embodiment, an appropriate polyamide resin may be selected in consideration of various characteristics of the polyamide resin, the purpose of the intended molded article, and the like.

Among the polyamide resins, a polyamide resin (xylylenediamine polyamide resin) containing a diamine-derived structural unit and a dicarboxylic acid-derived structural unit is preferable, wherein 70 mol% or more of the diamine-derived structural unit is derived from xylylenediamine and 70 mol% or more of the dicarboxylic acid-derived structural unit is derived from an α, ω -linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms.

In the xylylenediamine-based polyamide resin used in the present embodiment, the constituent unit derived from the diamine is preferably 80 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, still more preferably 99 mol% or more, of the constituent unit derived from the xylylenediamine.

The structural unit derived from the xylylenediamine is preferably a structural unit derived from the m-xylylenediamine and/or a structural unit derived from the p-xylylenediamine, more preferably comprises 50 to 90 mol% of the m-xylylenediamine and 10 to 50 mol% of the p-xylylenediamine (however, the total thereof is not more than 100 mol%), still more preferably comprises 60 to 80 mol% of the m-xylylenediamine and 20 to 40 mol% of the p-xylylenediamine. In the xylylenediamine-based polyamide resin used in the present embodiment, it is preferable that 95 mol% or more (preferably 99 mol% or more) of the structural units derived from xylylenediamine are structural units derived from m-xylylenediamine and/or structural units derived from p-xylylenediamine.

As diamines other than xylylenediamine, which can be used as a raw material diamine component of a xylylenediamine-based polyamide resin, there can be exemplified: aliphatic diamines such as tetramethylenediamine, pentamethylenediamine, 2-methylpentaenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2, 4-trimethylhexamethylenediamine, and 2, 4-trimethylhexamethylenediamine; alicyclic diamines such as 1, 3-bis (aminomethyl) cyclohexane, 1, 4-bis (aminomethyl) cyclohexane, 1, 3-diaminocyclohexane, 1, 4-diaminocyclohexane, bis (4-aminocyclohexyl) methane, 2-bis (4-aminocyclohexyl) propane, bis (aminomethyl) decalin, and bis (aminomethyl) tricyclodecane; diamines having an aromatic ring such as bis (4-aminophenyl) ether, p-phenylenediamine, and bis (aminomethyl) naphthalene may be used alone or in combination of two or more.

In the xylylenediamine-based polyamide resin used in the present embodiment, 70 mol% or more, preferably 75 mol% or more, more preferably 85 mol% or more, still more preferably 95 mol% or more, still more preferably 99 mol% or more of the constituent units derived from the dicarboxylic acid are derived from an α, ω -linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms.

Examples of the α, ω -linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms include succinic acid, glutaric acid, adipic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, and the like, and adipic acid and/or sebacic acid are preferable. The α, ω -linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms may be used alone or in combination of two or more.

Examples of the dicarboxylic acid component other than the α, ω -linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms include isophthalic acid, terephthalic acid, phthalic acid and other phthalic acid compounds, 1, 2-naphthalenedicarboxylic acid, 1, 3-naphthalenedicarboxylic acid, 1, 4-naphthalenedicarboxylic acid, 1, 5-naphthalenedicarboxylic acid, 1, 6-naphthalenedicarboxylic acid, 1, 7-naphthalenedicarboxylic acid, 1, 8-naphthalenedicarboxylic acid, 2, 3-naphthalenedicarboxylic acid, 2, 6-naphthalenedicarboxylic acid, and isomers of naphthalene dicarboxylic acid such as 2, 7-naphthalenedicarboxylic acid, and one or more of them may be used.

As one embodiment of the xylylenediamine polyamide resin, it is preferable that the xylylenediamine used as a raw material comprises 50 to 90 mol% of m-xylylenediamine and 10 to 50 mol% of p-xylylenediamine, and the alpha, omega-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms comprises adipic acid and/or sebacic acid. It is more preferable that 90 mol% or more of the raw diamine is xylylenediamine, the xylylenediamine contains 60 to 80 mol% of m-xylylenediamine and 40 to 20 mol% of p-xylylenediamine in total of 99 mol% or more, and 90 mol% or more of the α, ω -linear aliphatic dicarboxylic acid is adipic acid and/or sebacic acid.

The xylylenediamine polyamide resin used in the present embodiment is composed mainly of a diamine-derived structural unit and a dicarboxylic acid-derived structural unit, but the other structural units are not completely excluded, and of course, structural units derived from lactams such as epsilon-caprolactam and laurolactam, and aliphatic aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid may be contained. The main component is that the total number of the structural units derived from diamine and the structural units derived from dicarboxylic acid is the largest among the structural units constituting the xylylenediamine-based polyamide resin. In the present embodiment, the total of the diamine-derived structural units and the dicarboxylic acid-derived structural units in the xylylenediamine-based polyamide resin preferably occupies 90% or more, more preferably 95% or more of the total structural units.

The resin composition of the present embodiment preferably contains a crystalline thermoplastic resin (preferably a polyamide resin, more preferably a xylylenediamine polyamide resin) in an amount of 30 mass% or more of the resin composition, more preferably 35 mass% or more, still more preferably 40 mass% or more, and still more preferably 45 mass% or more. The upper limit of the content of the crystalline thermoplastic resin is preferably 80 mass% or less, more preferably 75 mass% or less.

The resin composition of the present embodiment may contain only one kind of crystalline thermoplastic resin, or may contain two or more kinds. In the case where two or more kinds are contained, the total amount is preferably within the above range.

< reinforcing filler >)

The resin composition of the present embodiment contains a reinforcing filler in a proportion of 10 to 120 parts by mass relative to 100 parts by mass of the crystalline thermoplastic resin. By containing the reinforcing filler in the above-described proportion, high mechanical strength can be achieved. The reinforcing filler in the present embodiment does not contain components corresponding to cerium oxide and a nucleating agent described later.

As the reinforcing filler in the present embodiment, a reinforcing material for plastic, which is commonly used, can be used, which has an effect of improving the mechanical properties of a resin composition obtained by blending the reinforcing filler in a resin. The reinforcing filler may be an organic or inorganic material, and is preferably an inorganic material. The reinforcing filler may be preferably fibrous reinforcing fillers such as glass fibers, carbon fibers, basalt fibers, wollastonite, and potassium titanate fibers. In addition, fillers such as granular or amorphous fillers such as calcium carbonate, titanium oxide, feldspar minerals, clay, organized clay, glass beads, and the like can also be used; glass flakes, mica, graphite, and the like. Among them, fibrous fillers, particularly glass fibers, are preferably used in terms of mechanical strength, rigidity and heat resistance. As the glass fiber, any glass fiber among glass fibers having a circular cross-sectional shape and glass fibers having a deformed cross-sectional shape can be used.

The reinforcing filler is more preferably one surface-treated with a surface treatment agent such as a coupling agent. The glass fiber to which the surface treatment agent is attached is preferable because it is excellent in durability, wet heat resistance, hydrolysis resistance, and thermal shock resistance.

The glass fiber includes glass compositions such as a glass, C glass, E glass, S glass, R glass, M glass, and D glass, and particularly preferably E glass (alkali-free glass).

The glass fiber is a glass fiber having a cross-sectional shape cut at right angles in the longitudinal direction, which is a perfect circle, a polygon, and a fibrous appearance.

The glass fibers used in the resin composition of the present embodiment may be single fibers or fibers obtained by twisting a plurality of single fibers.

The glass fiber may be any of "glass roving" obtained by continuously winding single fiber or a plurality of single fibers twisted together, "chopped strands" which are cut into a length of 1 to 10mm in order, and "milled fiber" which is pulverized into a length of 10 to 500 μm. The glass fibers are commercially available from Asahi Fiber Glass under the trade names "Glassron Chopped Strand" and "Glassron Milled Fiber". The glass fibers may also be combined with fibers of different morphologies.

The glass fiber used in the present embodiment may have a circular or non-circular cross section. By using glass fibers having a non-circular cross section, warpage of the obtained molded article can be more effectively suppressed. In addition, in the present embodiment, even if glass fibers having a circular cross section are used, warpage can be effectively suppressed.

The content of the reinforcing filler in the resin composition of the present embodiment is 10 parts by mass or more, preferably 20 parts by mass or more, more preferably 30 parts by mass or more, and still more preferably 40 parts by mass or more, relative to 100 parts by mass of the crystalline thermoplastic resin. The upper limit is preferably 120 parts by mass or less, more preferably 110 parts by mass or less, per 100 parts by mass of the crystalline thermoplastic resin.

The content of the reinforcing filler in the resin composition of the present embodiment is preferably 20 mass% or more, more preferably 25 mass% or more of the resin composition. The upper limit value is preferably 70 mass% or less, more preferably 65 mass% or less, further preferably 60 mass% or less, and further preferably 55 mass% or less.

The resin composition of the present embodiment may contain only one kind of reinforcing filler, or may contain two or more kinds. When two or more types are contained, the total amount is within the above range. The reinforcing filler content in the present embodiment includes the amounts of the bundling agent and the surface treating agent.

Light-transmitting dye having perylene skeleton

The resin composition of the present embodiment contains a light-transmitting dye having a perylene skeleton in a proportion of 0.01 to 1.0 parts by mass relative to 100 parts by mass of the crystalline thermoplastic resin. By incorporating a light-transmitting dye having a perylene skeleton, color migration to other members (particularly, absorbing resin members) can be effectively suppressed.

The light-transmitting pigment used in the present embodiment is preferably a black pigment or a pigment that is visually observable by human, such as melanin. The light-transmitting coloring matter includes the following coloring matters: at least one of crystalline thermoplastic resins (preferably polyamide resins, more preferably xylylenediamine polyamide resins), 30 mass% of glass fibers, and 0.2 mass% of pigments (pigments considered as light-transmitting pigments) are blended so that the total amount becomes 100 mass%, and the transmittance at a measurement wavelength of 1070nm is 20% or more.

The light-transmitting pigment may be a dye or a pigment, and is preferably a pigment.

Examples of pigments having a perylene skeleton include BASF Color & Effect Japan, spectrum K0087 (old name: lumogen (registered trademark) Black K0087, lumogen Black FK 4280), spectrum K0088 (old name: lumogen Black K0088, lumogen Black FK 4281), and the like.

The resin composition of the present embodiment contains 0.01 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.08 parts by mass or more, still more preferably 0.10 parts by mass or more, still more preferably 0.15 parts by mass or more, still more preferably 0.18 parts by mass or more, and particularly preferably 0.20 parts by mass or more of the light-transmitting pigment having a perylene skeleton per 100 parts by mass of the crystalline thermoplastic resin. The resin composition of the present embodiment contains 1.0 part by mass or less, preferably 0.8 part by mass or less, more preferably 0.6 part by mass or less, still more preferably 0.5 part by mass or less, and still more preferably 0.45 part by mass or less of the light-transmitting pigment having a perylene skeleton per 100 parts by mass of the crystalline thermoplastic resin.

The resin composition of the present embodiment may contain only one kind of light-transmitting dye having a perylene skeleton, or may contain two or more kinds. In the case where two or more kinds are contained, the total amount is preferably within the above range.

The resin composition of the present embodiment may contain a pigment other than the light-transmitting pigment having a perylene skeleton, but preferably does not substantially contain the pigment. Substantially not including means that, for example, the content of other pigments is less than 1 mass% of the content of the light-transmitting pigment having a perylene skeleton.

< copper Compound >)

The resin composition of the present embodiment may contain a copper compound. By using a copper compound, significantly excellent thermal aging resistance can be achieved.

As the copper compound used in the present embodiment, there can be exemplified: copper halide (e.g., copper iodide, copper bromide, copper chloride) and copper acetate are preferably selected from the group consisting of copper iodide, copper bromide, copper acetate, copper chloride and copper chloride, more preferably selected from the group consisting of copper iodide, copper acetate and copper chloride, and still more preferably copper iodide.

The copper compound is preferably used in combination with an alkali halide as described later. When the copper compound is combined with the alkali metal halide, a mixture of the copper compound and the alkali metal halide is preferably 1:1 to 1:15 (mass ratio), more preferably 1:1 to 1:5, and still more preferably 1:2 to 1:4.

In the case of combining the copper compound with the alkali metal halide, the contents of these are incorporated into the present specification by reference to the descriptions in paragraphs 0046 to 0048 of Japanese patent application laid-open No. 2013-513681.

The proportion of the copper compound in the resin composition of the present embodiment is preferably 0.01 to 1 mass%, more preferably 0.05 mass% or more, and still more preferably 0.5 mass% or less.

The resin composition of the present embodiment may contain only one kind of copper compound, or may contain two or more kinds. In the case where two or more kinds are contained, the total amount is preferably within the above range.

< alkali halide Metal >)

The resin composition of the present embodiment may contain an alkali metal halide. By using an alkali halide, the heat aging resistance and the wet heat resistance tend to be further improved.

The alkali halide used in the present embodiment means an alkali halide. The alkali metal is preferably potassium or sodium, more preferably potassium. The halogen atom is preferably iodine, bromine or chlorine, more preferably iodine. Specific examples of the alkali metal halide used in the present embodiment include potassium iodide, potassium bromide, potassium chloride and sodium chloride, and potassium iodide is preferable.

The proportion of the alkali metal halide in the resin composition of the present embodiment is preferably 0.01 to 1 mass%, more preferably 0.1 mass% or more, and still more preferably 0.5 mass% or less.

The resin composition of the present embodiment may contain only one kind of alkali metal halide, or may contain two or more kinds. In the case where two or more kinds are contained, the total amount is preferably within the above range.

< cerium oxide >)

The resin composition of the present embodiment preferably contains cerium oxide. By containing cerium oxide, color migration to other members (particularly, to an absorbing resin member to be laser welded) can be effectively suppressed even after being left under high-temperature, humid heat. Further, the cerium oxide has a relatively low mohs hardness, and therefore, it is less likely to damage reinforcing fillers such as glass fibers.

The cerium oxide in the present embodiment means cerium oxide having a purity of 90 mass% or more. That is, impurities may be contained in the cerium oxide. The cerium oxide used in the present embodiment is preferably cerium oxide having a lanthanum content of more than 0 mass% and 1 mass% or less as measured by ICP emission analysis, more preferably cerium oxide having a lanthanum content of 0.01 to 0.7 mass% as measured by ICP emission analysis, still more preferably cerium oxide having a lanthanum content of 0.02 to 0.4 mass% as measured by ICP emission analysis, and still more preferably cerium oxide having a lanthanum content of 0.05 to 0.2 mass% as measured by ICP emission analysis. By setting the range as described above, color migration to other members can be more effectively suppressed.

In this way, a desired amount of lanthanum can be easily blended into the resin composition by using cerium oxide containing lanthanum in a trace amount.

In this embodiment, the content of cerium in the cerium oxide is preferably 73 mass% or more, more preferably 75 mass% or more, and further preferably 77 mass% or more. The upper limit of the content of the cerium oxide is preferably 85 mass% or less, more preferably 83 mass% or less, and still more preferably 80 mass% or less.

The median particle diameter (particle size by laser diffraction scattering) of the cerium oxide used in the present embodiment is preferably 3 μm or less. The lower limit of the median diameter is, for example, 0.1 μm or more.

By using the cerium oxide having the above-mentioned median particle diameter, damage to the reinforcing filler can be effectively suppressed, and a resin composition having more excellent mechanical strength can be obtained.

The content of cerium oxide in the resin composition of the present embodiment is preferably 0.01 mass% or more, more preferably 0.05 mass% or more. The upper limit of the content of cerium oxide in the resin composition is preferably 5% by mass or less, more preferably 4% by mass or less, still more preferably 3% by mass or less, and still more preferably 2% by mass or less.

< Release agent >

The resin composition of the present embodiment may contain a release agent.

Examples of the release agent include: aliphatic carboxylic acids, salts of aliphatic carboxylic acids, esters of aliphatic carboxylic acids with alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15000, silicone oils, ketone waxes, light Amide, and the like, are preferable, aliphatic carboxylic acids, salts of aliphatic carboxylic acids, esters of aliphatic carboxylic acids with alcohols, and more preferable, salts of aliphatic carboxylic acids.

Details of the release agent can be referred to the descriptions in paragraphs 0055 to 0061 of Japanese patent application laid-open No. 2018-095706, and these descriptions are incorporated herein.

When the resin composition of the present embodiment contains a release agent, the content thereof in the resin composition is preferably 0.05 to 3% by mass, more preferably 0.1 to 0.8% by mass, and even more preferably 0.2 to 0.6% by mass.

The resin composition of the present embodiment may contain only one release agent, or may contain two or more release agents. In the case where two or more kinds are contained, the total amount is preferably within the above range.

< nucleating agent >

The resin composition of the present embodiment may contain a nucleating agent. By compounding the nucleating agent, crystallization can be promoted and solidification becomes easy, and thus the molding cycle can be improved. The nucleating agent is not particularly limited as long as it is a substance that does not melt during melt processing and is capable of forming crystalline nuclei during cooling, and among them, talc and calcium carbonate are preferable, and talc is more preferable.

The lower limit of the number average particle diameter of the nucleating agent is preferably 0.1 μm or more, more preferably 1 μm or more, and still more preferably 3 μm or more. The upper limit of the number average particle diameter of the nucleating agent is preferably 40 μm or less, more preferably 30 μm or less, further preferably 28 μm or less, further preferably 15 μm or less, further more preferably 10 μm or less.

The proportion of the nucleating agent in the resin composition of the present embodiment is preferably 0.01 to 1% by mass, more preferably 0.1% by mass or more, and still more preferably 0.5% by mass or less.

The resin composition of the present embodiment may contain only one kind of nucleating agent, or may contain two or more kinds. In the case where two or more kinds are contained, the total amount is preferably within the above range.

< other Components >)

The resin composition of the present embodiment may contain other components within a range not departing from the gist of the present embodiment. Examples of such additives include light stabilizers, antioxidants, ultraviolet absorbers, fluorescent brighteners, anti-dripping agents, antistatic agents, antifogging agents, antiblocking agents, fluidity improvers, plasticizers, dispersants, antibacterial agents, flame retardants, and the like. These components may be used alone or in combination of two or more.

In the resin composition of the present embodiment, the content of the crystalline thermoplastic resin, the reinforcing filler, the light-transmitting pigment having a perylene skeleton, and the content of at least one of the copper compound, the alkali halide, and the cerium oxide, and the other additives are adjusted so that the total amount of the components becomes 100 mass%. In this embodiment, a mode is exemplified in which the total of the crystalline thermoplastic resin, the reinforcing filler, the light-transmitting pigment having a perylene skeleton, the copper compound, at least one of an alkali metal halide and cerium oxide, the nucleating agent, and the mold release agent accounts for 99 mass% or more of the resin composition.

< lanthanum content in resin composition >)

The lanthanum content of the resin composition of the present embodiment is preferably more than 0 mass ppm and 150 mass ppm or less. By containing a trace amount of lanthanum in this way, color migration can be more effectively suppressed even after being left under high temperature and high humidity. Further, by setting 150 mass ppm or less, particularly 40 mass ppm or less, the tensile strength after being left under high temperature and high humidity can be maintained at a high level.

The lower limit value of the lanthanum content in the resin composition is preferably 0.01 mass ppm or more, more preferably 0.05 mass ppm or more, still more preferably 0.1 mass ppm or more, still more preferably 0.5 mass ppm or more, still more preferably 0.8 mass ppm or more, still more preferably 1 mass ppm or more, and particularly preferably 2 mass ppm or more.

The upper limit of the lanthanum content in the resin composition is preferably 40 mass ppm or less, more preferably 30 mass ppm or less, further preferably 25 mass ppm or less, further preferably 20 mass ppm or less, further preferably 15 mass ppm or less, further preferably 12 mass ppm or less, particularly preferably 8 mass ppm or less, and even more preferably 5 mass ppm or less.

In the resin composition of the present embodiment, lanthanum is generally blended in the form of lanthanum contained in cerium oxide.

Method for producing resin composition

The method for producing the resin composition of the present embodiment is not particularly limited, and a method using a single screw or twin screw extruder having a device capable of degassing from a vent is preferable as the kneading machine. The crystalline thermoplastic resin, the reinforcing filler, the light-transmitting pigment, at least one of copper iodide, potassium iodide and cerium oxide, and other additives blended as necessary may be supplied to a kneading machine together, or after the crystalline thermoplastic resin is supplied, other blending components may be sequentially supplied. In order to suppress breakage during kneading, it is preferable to supply the reinforcing filler from the middle of the extruder. Further, two or more components selected from the respective components may be mixed and kneaded in advance.

In this embodiment, the light-transmitting pigment may be prepared in advance by preparing a material which is subjected to masterbatch gelation with a crystalline thermoplastic resin or the like, and then kneading with other components (at least one of a crystalline thermoplastic resin, a reinforcing filler, a light-transmitting pigment, copper iodide, potassium iodide, and cerium oxide, or the like), thereby obtaining the resin composition of this embodiment.

The method for producing a molded article using the resin composition of the present embodiment is not particularly limited, and molding methods generally used for thermoplastic resins, that is, injection molding, blow molding, extrusion molding, compression molding, and the like can be applied. In this case, since fluidity is good, a molding method particularly preferred is injection molding. In injection molding, the temperature of the cylinder is preferably controlled to 250 to 300 ℃.

< composition combination >)

The resin composition of the present embodiment and the light-absorbing resin composition containing the thermoplastic resin and the light-absorbing pigment are preferably used as a composition, in particular, a composition for producing a molded article (laser deposited article) by laser deposition.

That is, the resin composition of the present embodiment contained in the composition functions as a light-transmitting resin composition, and a molded article formed from the light-transmitting resin composition serves as a laser-transmitting resin member at the time of laser welding. On the other hand, a molded article formed of the light-absorbent resin composition is a member that absorbs laser light during laser welding.

Light-absorbing resin composition

The light-absorbing resin composition used in the present embodiment contains a thermoplastic resin and a light-absorbing pigment. Other components such as reinforcing fillers may be included.

Examples of the thermoplastic resin include polyamide resins, olefin resins, vinyl resins, styrene resins, acrylic resins, polyphenylene ether resins, polyester resins, polycarbonate resins, polyacetal resins, and the like, and particularly preferred are crystalline thermoplastic resins, more preferred are polyamide resins and crystalline polyester resins, and further preferred are polyamide resins, from the viewpoint of good compatibility with the light-transmitting resin composition (the resin composition of the present embodiment). The thermoplastic resin may be one kind or two or more kinds.

The type of the polyamide resin used in the light-absorbing resin composition is not limited, and the crystalline thermoplastic resin is preferable.

Examples of the reinforcing filler include fillers capable of absorbing laser light, such as glass fibers, carbon fibers, silica, alumina, carbon black, and inorganic powders coated with a material for absorbing laser light, and glass fibers are preferable. The glass fibers have the same meaning as those that can be incorporated into the resin composition of the present embodiment. The content of the reinforcing filler is preferably 20 to 70% by mass, more preferably 25 to 60% by mass, and still more preferably 30 to 55% by mass.

As the light-absorbing dye, a dye having an absorption wavelength in a range of a laser wavelength to be irradiated is included, and for example, in the present embodiment, a dye having an absorption wavelength in a range of 900nm to 1100nm is included. The light-absorbing coloring matter includes the following coloring matters: for example, a dye having a transmittance of less than 30%, and further 10% or less when the transmittance is measured by a measurement method described in examples described later is blended in an amount of 0.3 parts by mass with respect to 100 parts by mass of the crystalline thermoplastic resin.

Specific examples of the light-absorbing pigment include black pigments such as inorganic pigments (e.g., acetylene black, lamp black, thermal black, furnace black, channel black, ketjen black, etc.), red pigments such as iron oxide red, orange pigments such as molybdenum orange, white pigments such as titanium oxide, and organic pigments (yellow pigments, orange pigments, red pigments, blue pigments, green pigments, etc.). Among them, inorganic pigments are generally strong in hiding power, and thus, black pigments are preferable, and further preferable. These light-absorbing pigments may be used in combination of two or more. The content of the light-absorbing pigment is preferably 0.01 to 30 parts by mass relative to 100 parts by mass of the crystalline thermoplastic resin.

In the above composition combination, the components other than the light-transmitting pigment and the reinforcing filler in the resin composition and the components other than the light-absorbing pigment and the reinforcing filler in the light-absorbing resin composition are preferably used in common at least 80 mass%, more preferably at least 90 mass%, and still more preferably 95 to 100 mass%.

Laser cladding method

Next, a laser welding method will be described. In the present embodiment, a molded article (a transmissive resin member) formed from the resin composition of the present embodiment and a molded article (an absorptive resin member) formed from the light-absorbing resin composition can be laser welded to manufacture a molded article. By performing laser welding, the transmissive resin member and the absorptive resin member can be firmly welded without using an adhesive.

The shape of the members is not particularly limited, and since the members are used by joining them together by laser welding, the members are generally in a shape having at least a surface contact portion (flat surface, curved surface). In the laser welding, laser light transmitted through the transmissive resin member is absorbed by the absorptive resin member, and the absorptive resin member is melted to weld the two members. In particular, the absorptive resin member melts and transfers heat to the transmissive member, thereby welding the both members. The molded article formed from the resin composition of the present embodiment has high transmittance to laser light, and thus can be preferably used as a transmissive resin member. Here, the thickness of the laser light transmitting member (the thickness of the laser light transmitting portion in the laser light transmitting direction) may be appropriately determined in consideration of the application, the composition of the resin composition, and others, and is, for example, 5mm or less, preferably 4mm or less.

The laser source used for laser welding may be determined by the absorption wavelength of light of the light-absorbing dye, and is preferably a laser having a wavelength in the range of 900 to 1100nm, and for example, a semiconductor laser or a fiber laser may be used.

More specifically, for example, when the transmission resin member and the absorption resin member are welded, first, the portions to be welded are brought into contact with each other. In this case, the welding portions of the two are preferably in surface contact, and may be a plane-to-plane surface, a curved surface-to-curved surface, or a combination of a plane and a curved surface. Then, laser light is irradiated from the transmissive resin member side. In this case, the laser light may be focused on the interface between the two by a lens as necessary. The condensed beam is transmitted to the transmissive resin member, and is absorbed in the vicinity of the surface of the absorptive resin member to generate heat, thereby melting. Then, the heat is transferred to the transmissive resin member by heat transfer, and a molten pool is formed at the interface between the transmissive resin member and the transmissive resin member, and after cooling, the transmissive resin member and the molten pool are joined.

The molded article obtained by welding the transmissive resin member and the absorptive resin member as described above has high welding strength. The molded article of the present embodiment includes a member forming a part of the finished product or the component, in addition to the finished product or the component.

The molded article obtained by laser welding in the present embodiment has good mechanical strength, high welding strength, and little resin damage due to laser irradiation, and thus can be applied to various applications such as various storage containers, electric/electronic equipment components, office Automation (OA) equipment components, home electric equipment components, mechanical equipment components, and vehicle equipment components. In particular, the present invention can be preferably used for food containers, pharmaceutical containers, fat and oil product containers, hollow parts for vehicles (various containers, intake manifold parts, camera housings, etc.), motor parts for vehicle electric parts (various control units, ignition coil parts, etc.), various sensor parts, connector parts, switch parts, current breaker parts, relay parts, coil parts, transformer parts, lamp parts, etc. The resin composition and the composition combination of the present invention are particularly suitable for an in-vehicle camera module. In particular, the in-vehicle camera component formed of the resin composition and the composition combination of the present embodiment is suitable for an in-vehicle camera.

Examples

Hereinafter, the present invention will be described more specifically with reference to examples. The materials, amounts, ratios, processing contents, processing steps and the like shown in the following examples may be appropriately changed without departing from the gist of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

When the measurement apparatus and the like used in the examples are difficult to obtain due to production stoppage and the like, the measurement may be performed using other apparatuses having the same performance.

< Polyamide resin >)

MP10: the molar ratio of M-xylylenediamine to P-xylylenediamine (M/P) =7:3 was synthesized in accordance with the following synthesis examples.

Synthesis example of "MP 10 (M/P molar ratio=7:3) >

After sebacic acid was dissolved by heating in a reaction tank in a nitrogen atmosphere, the contents were stirred, and a mixed diamine having a molar ratio of 3:7 of terephthalamide (Mitsubishi gas chemical Co., ltd.) to isophthalamide (Mitsubishi gas chemical Co., ltd.) was slowly added dropwise under pressure (0.35 MPa) so that the molar ratio of diamine to sebacic acid became about 1:1, and the temperature was raised to 235 ℃. After the completion of the dropwise addition, the reaction was continued for 60 minutes to adjust the component amounts having a molecular weight of 1000 or less. After the completion of the reaction, the content was taken out in the form of strands, and pelletized with a pelletizer to obtain a polyamide resin (MP 10).

MP6: M/P molar ratio=7:3, the synthesis was performed according to the following synthesis example.

Synthesis example of MP6 (M/P molar ratio=7:3) >

After adipic acid (manufactured by RHODIA) was dissolved by heating in a reaction tank under nitrogen atmosphere, the content was stirred, and a mixed diamine having a molar ratio of 3:7 of terephthalamide (manufactured by mitsubishi gas chemical Co., ltd.) to isophthalamide (manufactured by mitsubishi gas chemical Co., ltd.) was slowly added dropwise under pressure (0.35 MPa) so that the molar ratio of diamine to adipic acid became about 1:1, and the temperature was raised to 270 ℃. After the completion of the dropwise addition, the pressure was reduced to 0.06MPa, and the reaction was continued for 10 minutes to adjust the component amount of 1000 or less in molecular weight. Then, the content was taken out in the form of strands, and pelletized with a pelletizer to obtain a polyamide resin (MP 6).

PA66: polyamide 66, manufactured by INVISTA Nylon Polymer Co., ltd., INVISTA U4800

< Talc >

#5000S: lin Huacheng from Micron White

Copper iodide (CuI) >

Japanese chemical industry Co Ltd

< Potassium iodide >)

Fuji Film Wako Pure Chemical Industries Co Ltd

< Zinc (II) stearate >, and method for preparing the same

Fuji Film Wako Pure Chemical Industries Co Ltd

< Release agent >

CS8CP: montanic acid soap manufactured by Nidong chemical industry Co., ltd

< cerium oxide >)

Cerium oxide 1: cerium oxide with purity of 90% by mass or more, manufactured by Treibacher Industrie Japan Co., ltd., cerium Oxide Hydrate 90.90, cerium content of 72.1% by mass, lanthanum content of 4.4% by mass, median particle diameter (particle size by laser diffraction scattering method) of 2 μm or less

Cerium oxide 2: cerium oxide with purity of 90 mass% or more, cerium hydrochloride 90 manufactured by Treibacher Industrie Japan Co., ltd., cerium content of 78.5 mass%, lanthanum content of 0.1 mass%, and median particle diameter (particle size by laser diffraction scattering method) of 3 μm or less

< analysis of lanthanum and cerium content in cerium oxide >

The sample was dried by heating at 120℃for 2 hours in the atmosphere. 100mg of a sample is precisely weighed, perchloric acid, hydrogen peroxide and water are added, and after the sample is heated and decomposed, water is added to reach a certain volume. The solution was diluted, and Ce was quantified by ICP emission analysis (ICP-AES) using an acid concentration matching calibration curve method, and La was quantified by a standard addition calibration curve method.

< light-transmitting pigment >

Lumogen 4281 (K0088): perylene pigment, lumogen (registered trademark) Black K0088 (old Lumogen Black FK 4281) manufactured by BASF Color & Effect Japan Co., ltd

LTW-8701H: orient Chemical Industries company, solventRed179 0.46 mass%, solventYellow 163 0.23 mass% and AcidBlue 80.53 mass%

LTW-8731H: orient Chemical Industries, soventRed179 1.56 mass%, acidBlue 80.48 mass%

< reinforcing filler >)

ECS03T-211H: glass fiber of E glass, manufactured by Nippon electric Nitro Co., ltd., weight average fiber diameter of 10.5 μm, cut length of 3.5mm

Example 1

< Compounds >

The components other than the reinforcing filler were weighed so as to have the composition shown in Table 1 (the components shown in Table 1 are parts by mass) described below, and fed from the screw root of a twin-screw extruder (TEM 26SS, toshiba instruments Co., ltd.) using a twin-screw box weigh feeder (manufactured by KUBOTA Co., ltd.). Further, the reinforcing filler was fed into the twin-screw extruder described above from the side of the extruder using a vibrating box-type weigh feeder (CE-V-1B-MP, manufactured by kuota corporation), and melt-kneaded with a resin component or the like to obtain resin composition pellets. The temperature of the extruder was set at 280 ℃.

After the pellets obtained above were dried at 120℃for 4 hours, a No. 4 sheet (1.5 mm thick) according to ASTM D638 was produced using an injection molding machine (manufactured by Japanese Steel, clamping pressure 50T injection molding machine J-50 ADS).

< color migration test after being placed under high temperature and high humidity >)

In example 1, a number 4 sheet (1.5 mm thick) (target member) according to ASTM D638 was produced by mixing, extruding and injection molding in the same manner as the other components except for the light-transmitting pigment.

The sheet No. 4 based on ASTM D638, which was obtained from the resin pellet described in example 1, was superimposed on the target member and fixed with a jig. Then, the mixture was allowed to stand at 85℃and a relative humidity of 85% for 50 hours and 1000 hours. After standing, the presence or absence of color migration of the light-transmitting dye to the target member was visually confirmed, and the evaluation was performed on 5 grades of A to E. The case where color migration was not confirmed is designated as a, and the case where color migration was most serious is designated as E. In the judgment, the degree of color migration of the test piece after the laser deposited material of comparative example 2 was left standing at 85℃and a relative humidity of 85% for 1000 hours was defined as D, and the judgment was made based on this. The evaluation was performed by 10 experts and determined with a plurality of tickets.

Examples 2 to 36 and comparative examples 1 to 18

In example 1, the amounts of the raw materials were changed as shown in tables 1 to 6 (the amounts of the respective components shown in tables 2 to 6 are shown in parts by mass), and pellets of a resin composition and No. 4 tablets (1.5 mm thick) based on ASTM D638 were obtained. At this time, the temperature of the extruder was set to 280℃in the case of using MP6 as the polyamide resin and 280℃in the case of using PA 66.

The color migration test after the storage under high temperature and high humidity was performed in the same manner as in example 1. In example 2, the target member was obtained in the same manner as the resin composition described in example 2 except for the light-transmitting pigment. In example 3, the target member was obtained in the same manner as in example 3 except for the light-transmitting pigment. The same applies to examples 4 to 36 and comparative examples 1 to 18.

The lanthanum amount in the resin composition was calculated from the lanthanum amount derived from cerium oxide. The lanthanum content of other components is below the detection limit.

From the above results, it is clear that the resin composition of the present invention effectively suppresses color migration. In contrast, when a dye other than the light-transmitting dye having a perylene skeleton is used, the degree of color migration is high.

Claims

1. A light-transmitting resin composition for laser welding, comprising, per 100 parts by mass of a crystalline thermoplastic resin:

10 to 120 parts by mass of reinforcing filler,

0.01 to 1.0 parts by mass of a light-transmitting dye having a perylene skeleton

Cerium oxide having a lanthanum content of more than 0 mass% and 1 mass% or less as measured by ICP emission spectrometry.

2. The resin composition according to claim 1, wherein,

3. The resin composition of claim 1, further comprising at least one of a copper compound and an alkali metal halide.

4. The resin composition of claim 2, further comprising at least one of a copper compound and an alkali metal halide.

5. The resin composition according to claim 1, wherein

The content of cerium oxide in the resin composition is 0.01 to 5 mass%.

6. The resin composition according to claim 2, wherein

The content of cerium oxide in the resin composition is 0.01 to 5 mass%.

7. The resin composition according to claim 3, wherein

The content of cerium oxide in the resin composition is 0.01 to 5 mass%.

8. The resin composition according to claim 4, wherein

The content of cerium oxide in the resin composition is 0.01 to 5 mass%.

9. The resin composition according to any one of claims 1 to 8, wherein,

the crystalline thermoplastic resin comprises a polyamide resin.

10. The resin composition according to claim 9, wherein,

the polyamide resin comprises structural units derived from diamine and structural units derived from dicarboxylic acid, wherein 70 mol% or more of the structural units derived from diamine are derived from xylylenediamine, and 70 mol% or more of the structural units derived from dicarboxylic acid are derived from an alpha, omega-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms.

11. The resin composition according to any one of claims 1 to 8, wherein,

the light-transmitting pigment having a perylene skeleton is a pigment.

12. The resin composition according to claim 9, wherein,

the light-transmitting pigment having a perylene skeleton is a pigment.

13. The resin composition according to claim 10, wherein,

the light-transmitting pigment having a perylene skeleton is a pigment.

14. A composition combination having:

the resin composition according to any one of claims 1 to 13

15. A molded article formed from the resin composition according to any one of claims 1 to 13 or the composition according to claim 14.

16. The molded article according to claim 15, which is an in-vehicle camera component.

17. An in-vehicle camera comprising the molded article of claim 16.

18. A method for producing a molded article, the method comprising:

a molded article comprising the resin composition according to any one of claims 1 to 13, and a molded article comprising a light-absorbing resin composition comprising a thermoplastic resin and a light-absorbing pigment are laser welded.